Pre-clinical study of human umbilical cord mesenchymal stem cell transplantation for the treatment of traumatic brain injury: safety evaluation from immunogenic and oncogenic perspectives

Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells

In this editorial, we offer our perspective on the groundbreaking study entitled "Hypoxia and inflammatory factor preconditioning enhances the immunosuppressive properties of human umbilical cord mesenchymal stem cells", recently published in World Journal of Stem Cells. Despite over three decades of research on the clinical application of mesenchymal stem cells (MSCs), only a few therapeutic products have made it to clinical use, due to multiple preclinical and clinical challenges yet to be addressed. The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics, which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs. As we delve deeper into the intricacies of pretreatment methodologies, we anticipate a transformative shift in the landscape of MSC-based therapies, ultimately contributing to improved patient outcomes and advancing the field as a whole.

Preliminary study on mesenchymal stem cells in repairing nerve injury in pelvic floor denervation

Introduction: Nerve injury is considered one of the causes of pelvic floor dysfunction. Mesenchymal stem cells (MSCs) transplantation provides new possibilities for refractory degenerative diseases. This study aimed to explore the possibility and strategy of mesenchymal stem cells in treating pelvic floor dysfunction nerve injury. Methods: MSCs were isolated from human adipose tissue and cultured. A MSCs suspension (40 µL at 5 × 107/mL) was loaded on a gelatin scaffold. A rat model of anterior vaginal wall nerve injury was established by bilateral pudendal nerve denervation. The nerve tissue repair effect of mesenchymal stem cells transplanted into the anterior vaginal wall of a rat model was explored and compared in the following three groups: blank gelatin scaffold group (GS group), mesenchymal stem cell injection group (MSC group), and mesenchymal stem cells loaded on the gelatin scaffold group (MSC-GS group). Nerve fiber counting under a microscope and mRNA expression of neural markers were tested. Moreover, mesenchymal stem cells were induced into neural stem cells in vitro, and their therapeutic effect was explored. Results: Rat models of anterior vaginal wall nerve injury induced by bilateral pudendal nerve denervation showed a decreased number of nerve fibers in the anterior vaginal wall. qRT-PCR revealed that the content of neurons and nerve fibers in the rat model began to decrease 1 week after the operation and this could continue for 3 months. In vivo experiments showed that MSC transplantation improved the nerve content, and MSCs loaded on the gelatin scaffold had an even better effect. mRNA expression analysis demonstrated that MSCs loaded on gelatin scaffolds induced a higher and earlier gene expression of neuron-related markers. Induced neural stem cell transplantation was superior in improving the nerve content and upregulating the mRNA expression of neuron-related markers in the early stage. Conclusion: MSCs transplantation showed a promising repair capacity for nerve damage in the pelvic floor. The supporting role of gelatin scaffolds might promote and strengthen the nerve repair ability at an early stage. Preinduction schemes could provide an improved regenerative medicine strategy for innervation recovery and functional restoration in pelvic floor disorders in the future.

Bone marrow mesenchymal stem cell-derived exosome miR-29b-3p alleviates UV irradiation-induced photoaging in skin fibroblast

BACKGROUND

Mesenchymal stem cells-derived exosome (MSCs-exo) was identified to reduce photoaging. The purpose of this study was to investigate the potential role of microRNA (miR)-29b-3p derived from bone marrow MSCs-exo (BMSCs-exo) in photoaging.

METHODS

Exosomes were isolated from BMSCs and verified by Western blot. A photoaging cell model was constructed by UVB irradiation of human dermal fibroblasts (HDFs). Quantitative real-time PCR (RT-qPCR) was performed to detect the mRNA levels of miR-29b-3p, collagen type I and matrix metalloproteinases (MMPs). CCK-8, Transwell and flow cytometry were applicated to examine cell viability, migration and apoptosis. Commercial kits are used to measure levels of oxidative stress indicators. Finally, a dual-luciferase reporter assay was applied to validate the target of miR-29b-3p.

RESULTS

Extracted exosomes were positive for HSP70 and CD9. Survival of HDFs increased in an exosome concentration-dependent manner. UVB irradiation inhibited miR-29b-3p levels compared with controls, but BMSCs-exo treatment restored miR-29b-3p levels (p < .05). Additionally, BMSCs-exo-miR-29b-3p reversed the inhibition of HDFs migration and oxidative stress by UVB irradiation, as well as the promotion of apoptosis. However, this reversal was attenuated by the suppression of miR-29b-3p (p < .05). Furthermore, BMSCs-exo-miR-29b-3p also inhibited the degradation of collagen type I and the production of MMPs in photoaging, and they were also eliminated by the reduced miR-29b-3p. Finally, MMP-2 was the target gene of miR-29b-3p.

CONCLUSION

Our study presented a novel role for BMSCs-exo-miR-29b-3p in improving skin photoaging function, and these findings may provide new insights into the targeted treatment of skin photoaging.

RNA-Sequencing approach for exploring the therapeutic effect of umbilical cord mesenchymal stem/stromal cells on lipopolysaccharide-induced acute lung injury

Acute lung injury (ALI) is significantly associated with morbidity and mortality in patients with critical diseases. In recent years, studies have identified that mesenchymal stem/stromal cells (MSCs) ameliorate ALI and pulmonary fibrosis. However, the mechanism underlying this outcome in ALI has not yet been investigated. In this study, RNA sequencing technology was used to analyze the gene expression profile of lung tissue in lipopolysaccharide (LPS)-induced ALI rats following treatment with human umbilical cord MSC (HUCMSC). Differential expression analyses, gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes enrichment, protein–protein interaction network identification, and hub gene analysis were also performed. HUCMSC treatment decreased inflammatory factor production and alveolar exudates, and attenuated lung damage in LPS-induced ALI rats. The RNA-Seq data indicated that HUCMSC treatment activated the IL-17, JAK-STAT, NF-κB, and TNF-α signaling pathways, increased oxygen transport, and decreased extracellular matrix organization. HUCMSC exert beneficial effects on ALI via these signaling pathways by reducing inflammation, inhibiting pulmonary fibrosis, and improving lung ventilation. Moreover, our study further revealed the hub genes (Tbx2, Nkx2-1, and Atf5) and signaling pathways involved in HUCMSC treatment, thus providing novel perspectives for future research into the molecular mechanisms underlying cell treatment of ALI. HUCMSC can regulate multiple genes and signaling pathways, which can prevent LPS-induced lung damage in an ALI rat model.

Stem cell therapy as a promising strategy in necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease that affects newborns, particularly preterm infants, and is associated with high morbidity and mortality. No effective therapeutic strategies to decrease the incidence and severity of NEC have been developed to date. Stem cell therapy has been explored and even applied in various diseases, including gastrointestinal disorders. Animal studies on stem cell therapy have made great progress, and the anti-inflammatory, anti-apoptotic, and intestinal barrier enhancing effects of stem cells may be protective against NEC clinically. In this review, we discuss the therapeutic mechanisms through which stem cells may function in the treatment of NEC.

Therapeutic Application of Stem Cells in the Repair of Traumatic Brain Injury

Traumatic brain injury is the main cause of injury-related deaths and disabilities throughout the world, which is characterized by a disruption of the normal physiology of the brain following trauma. It can potentially cause severe complications such as physical, cognitive, and emotional impairment. In addition to understanding traumatic brain injury pathophysiology, this review explains the therapeutic potential of stem cells following brain injury in two pathways: response of endogenous neurogenic cells and transplantation of exogenous stem cell therapy. After traumatic brain injuries, clinical evidence indicated that endogenous neural progenitor cells might play an important role in regenerative medicine to treat brain injury. This is due to an increased neurogenic regeneration ability of these cells following brain injury. Besides, exogenous stem cell transplantation has also accelerated immature neuronal development and increased endogenous cellular proliferation in the damaged brain region. Therefore, a better understanding of the endogenous neural stem cell’s regenerative ability and the effect of exogenous stem cells on proliferation and differentiation ability may help researchers to understand how to increase functional recovery and tissue repair following injury.

Mesenchymal stem cells for the treatment of cognitive impairment caused by neurological diseases

Patients with neurological diseases often have cognitive impairment, which creates a substantial emotional and economic burden for patients and their families. This issue urgently needs to be addressed. The pathological mechanism of this cognitive impairment is a complicated process that involves a variety of cells and molecules, central nervous system inflammatory reactions, oxidative stress, free radical damage and nerve protection factor-related metabolic disorders. Traditional treatments include neuroprotective agents and analgesic therapy. However, analgesic therapy cannot improve cognitive function, and the blood-brain barrier (BBB) largely blocks neuroprotective agents from entering the central nervous system; therefore, it is very important to find a more effective treatment. Mesenchymal stem cells (MSCs) have anti-inflammatory, anti-apoptotic and immunomodulatory properties and have been proven to play an important role in the treatment of many neurodegenerative diseases. Most importantly, MSCs are likely to cross the BBB. Therefore, MSC therapy is regarded as an important means of ameliorating neurological impairment. The purpose of this review is to summarize recent researches on the treatment of cognitive dysfunction caused by neurological diseases with MSCs.

Secondary Mechanisms of Neurotrauma: A Closer Look at the Evidence

Traumatic central nervous system injury is a leading cause of neurological injury worldwide. While initial neuroresuscitative efforts are focused on ameliorating the effects of primary injury through patient stabilization, secondary injury in neurotrauma is a potential cause of cell death, oxidative stress, and neuroinflammation. These secondary injuries lack defined therapy. The major causes of secondary injury in neurotrauma include endoplasmic reticular stress, mitochondrial dysfunction, and the buildup of reactive oxygen or nitrogenous species. Stress to the endoplasmic reticulum in neurotrauma results in the overactivation of the unfolded protein response with subsequent cell apoptosis. Mitochondrial dysfunction can lead to the release of caspases and the buildup of reactive oxygen species; several characteristics make the central nervous system particularly susceptible to oxidative damage. Together, endoplasmic reticulum, mitochondrial, and oxidative stress can have detrimental consequences, beginning moments and lasting days to months after the primary injury. Understanding these causative pathways has led to the proposal of various potential treatment options.